Artificial tooth



H. 0. COWDRICK. ARTIHCIAL TooTH.

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Patented Aug. 30, 1921.

UNITED STATES HIB-Alf 0. COWDRICK, OF il?IzlIlLAlDELLPHIA, AIPENNS.YLVANIAa y ARTIFICIAL Toorn.. y

Specification of Letters Patent.

Patented Aug. 30,

i Application led November 29, 1920. Serial No. 427,172.

To all whom t may concern:

Be it known that I, HIRAM O. Cowpnici, a citizen of the United States, residing in the city and county of Philadelphia, State of Pennsylvania, have invented a new and useful Artificial Tooth, of which the following is a specification. v n

My invention consists of an artificial tooth provided with a projecting rib on the back thereof, and a metallic device adapted .to form a strong sheath or incasement for said rib, said device-being provided with means embedded in the body of the tooth and so firmly connected therewith and retained reliably in position in the biscuiting of the tooth.

The invention is satisfactorily illustrated in the accompanying drawing, but the important instrumentalities thereof may be varied, and so it is to be understood that the invention is not limited to the specific details shown and described, as long as they are within the spirit or scope of the claims.

Figure 1 represents a perspective view of an artificial tooth embodying my invention. f Fig. 2 represents a transverse section thereof on line 2-2 Fig. l. v

Fig. 3 represents a perspective viewof the tooth in primary condition.

Fig. 4 represents a perspective view of the sheath or inca-sement employed in primary condition.

Similar numerals ofv reference indicate corresponding parts in the figures.

Referring to the drawings,

l designates an artiiicial tooth on the back of which is the rib or tongue 2 which extends outwardly therefrom in the direction of the vertical axis of the tooth and is an integral member thereof imparting strength and stability to the tooth especially where it joins the same, the sides of said rib extending inclined from its rear face to its place of junction with the back of the tooth thus making the sides of the rib undercut.

3 designates a sheath consisting of a channeledbody of suitable metal, which is adapted to envelop the rear face and sides of said rib and is formed of the rear wall 4 and the side walls 5, the latter extending inclined from said wall to the back of the tooth so as to accord with the undercut sides of the rib, and thus form a dovetailed joint with said sides and so connecting the sheath with the rib and vice versa serving to strengthen said rib, the latter as sheathed being adapted subsequently to be embedded in the material of the mouth plate.

On the forward terminals of the side walls 5 of the sheath are the tongues 6 which enter the tooth from the back thereof at the base of the rib and, are embedded therein, as shown in Fig. 2, thus firmly connecting said sheath with the tooth and retaining it on the rib. In order to increase the holding action of said tongues 6 on the tooth, they are staggered in the direction of the length of the sheath on the opposite side walls thereof. The tooth is manufactured with the rib thereon and the sheath is placed over the latter and the tongues 6 are inserted in the soft material of theV tooth from the back thereof. Then the tooth with its appurtenances are biscuited and so the tooth has the l-ib,fsheath and tongues connected therewit It is evident that when the body of plastic material of which the tooth is formed is placed in the mold, the sheath may be applied to the back of said body and pressed thereonto into the adjacent portions of the plastic material thus forming the rib 2 by said sheath as a mold therefor, the tongues G also being forced into said material. Then the tooth is biscuited or baked with the result hereinbefore st ated. The sheath is not necessarilyI metal as it may be Vformed of porcelain or other sufficient hard material so that it incases the rib and reinforces the same and so serves to prevent the rib from being broken ofi" at its narrow end or neck where it joins the body of the tooth.

Having thus described my invention what I claim as new and desire to secure by Letters Patent, is

`1. An artificial tooth having on the back thereof a rearwardly projecting rib with undercut sides, and a sheath consisting of a back and sides forming a channeled body adapted to incase said rib, said sides having thereon forwardly projecting tongues which are embedded in the tooth forward of the base of said rib.

2. In an artificial tooth having on the back thereof, a rearwardly projecting rib, the latter having its sides undercut, a protecting shield for said rib adapted to incase the same, said shield having on the side walls thereof tongues projecting forward therefrom and staggered on the opposite side Walls and embedded in the tooth adapted sides adapted to enter the tooth and to be to cornect said fsheath with thiel tooth. f secured therein.

3. s eath or a rib on t e rear o an artcial tooth, the same consisting of a u HIRAMO# COWDRICK' 5 channeled body formed of a back and in- Witnesses:

olned sides adapted to incase said rib, 'and VJOHN A. WIEDERSHEIM, tongues projecting forwardly from said ll\T.BUssI1-IGER. 

